coding-agent/s14_cron_scheduler/code.py

#!/usr/bin/env python3
"""
s14: Cron 调度器 — 独立守护线程 + 队列处理器。

运行:  python s14_cron_scheduler/code.py
需要: pip install anthropic python-dotenv + .env 中配置 ANTHROPIC_API_KEY

相对 s13 的变化：
  - Cron任务 dataclass（id、cron、prompt、recurring、durable）
  - cron_matches：带 DOM/DOW OR 语义的 5 字段 cron 表达式匹配
  - schedule_job / cancel_job：注册/移除 cron 任务（带校验）
  - cron_scheduler_loop：独立守护线程，每 1 秒轮询
  - cron_queue：线程安全队列，调度器写入，队列处理器负责投递
  - queue_processor_loop：当 cron_queue 有任务时自动运行 agent_loop
  - 持久化存储：.scheduled_tasks.json（重启后仍保留）
  - 3 个新工具：schedule_cron、list_crons、cancel_cron

四层结构：
  1. 调度器：守护线程检查时间 → 触发匹配任务
  2. 队列：cron_queue 将调度器与 Agent 循环解耦
  3. 队列处理器：当队列中有任务且 Agent 空闲时唤醒 Agent
  4. 消费者：agent_loop 消费队列任务，并注入到 messages
"""

import os, subprocess, json, time, random, threading
from pathlib import Path
from datetime import datetime
from dataclasses import dataclass, asdict

try:
    import readline
    readline.parse_and_bind('set bind-tty-special-chars off')
except ImportError:
    pass

from anthropic import Anthropic
from dotenv import load_dotenv

load_dotenv(override=True)
if os.getenv("ANTHROPIC_BASE_URL"):
    os.environ.pop("ANTHROPIC_AUTH_TOKEN", None)

WORKDIR = Path.cwd()
MEMORY_DIR = WORKDIR / ".memory"
MEMORY_INDEX = MEMORY_DIR / "MEMORY.md"
client = Anthropic(base_url=os.getenv("ANTHROPIC_BASE_URL"))
MODEL = os.environ["MODEL_ID"]

# ── 任务系统 （来自 s12，已同步） ──

TASKS_DIR = WORKDIR / ".tasks"
TASKS_DIR.mkdir(exist_ok=True)


@dataclass
class Task:
    id: str
    subject: str
    description: str
    status: str          # pending | in_progress | completed
    owner: str | None
    blockedBy: list[str]


def _task_path(task_id: str) -> Path:
    return TASKS_DIR / f"{task_id}.json"


def create_task(subject: str, description: str = "",
                blockedBy: list[str] | None = None) -> Task:
    task = Task(
        id=f"task_{int(time.time())}_{random.randint(0, 9999):04d}",
        subject=subject, description=description,
        status="pending", owner=None,
        blockedBy=blockedBy or [],
    )
    save_task(task)
    return task


def save_task(task: Task):
    _task_path(task.id).write_text(json.dumps(asdict(task), indent=2))


def load_task(task_id: str) -> Task:
    return Task(**json.loads(_task_path(task_id).read_text()))


def list_tasks() -> list[Task]:
    return [Task(**json.loads(p.read_text()))
            for p in sorted(TASKS_DIR.glob("task_*.json"))]


def get_task(task_id: str) -> str:
    """以 JSON 返回完整任务详情。"""
    task = load_task(task_id)
    return json.dumps(asdict(task), indent=2)


def can_start(task_id: str) -> bool:
    """检查所有 blockedBy 依赖是否已完成；缺失依赖视为阻塞。"""
    task = load_task(task_id)
    for dep_id in task.blockedBy:
        if not _task_path(dep_id).exists():
            return False
        if load_task(dep_id).status != "completed":
            return False
    return True


def claim_task(task_id: str, owner: str = "agent") -> str:
    task = load_task(task_id)
    if task.status != "pending":
        status = {"pending": "待处理", "in_progress": "进行中",
                  "completed": "已完成"}.get(task.status, task.status)
        return f"任务 {task_id} 当前状态为 {status}，无法认领"
    if not can_start(task_id):
        deps = [d for d in task.blockedBy
                if not _task_path(d).exists() or load_task(d).status != "completed"]
        return f"被阻塞于：{deps}"
    task.owner = owner
    task.status = "in_progress"
    save_task(task)
    print(f"  \033[36m[认领] {task.subject} → in_progress（负责人：{owner}）\033[0m")
    return f"已认领 {task.id} ({task.subject})"


def complete_task(task_id: str) -> str:
    task = load_task(task_id)
    if task.status != "in_progress":
        status = {"pending": "待处理", "in_progress": "进行中",
                  "completed": "已完成"}.get(task.status, task.status)
        return f"任务 {task_id} 当前状态为 {status}，无法完成"
    task.status = "completed"
    save_task(task)
    unblocked = [t.subject for t in list_tasks()
                 if t.status == "pending" and t.blockedBy and can_start(t.id)]
    print(f"  \033[32m[完成] {task.subject} ✓\033[0m")
    msg = f"已完成 {task.id} ({task.subject})"
    if unblocked:
        msg += f"\n已解除阻塞：{', '.join(unblocked)}"
        print(f"  \033[33m[已解除阻塞] {', '.join(unblocked)}\033[0m")
    return msg


# ── 提示词组装 （来自 s10，已同步） ──

PROMPT_SECTIONS = {
    "identity": "你是一个编码 Agent。直接行动，不要只解释。",
    "tools": "可用工具：bash, read_file, write_file, "
             "create_task, list_tasks, get_task, claim_task, complete_task, "
             "schedule_cron, list_crons, cancel_cron.",
    "workspace": f"工作目录：{WORKDIR}",
    "memory": "有可用的相关记忆时，会在下方注入。",
}


def assemble_system_prompt(context: dict) -> str:
    sections = [PROMPT_SECTIONS["identity"],
                PROMPT_SECTIONS["tools"],
                PROMPT_SECTIONS["workspace"]]
    memories = context.get("memories", "")
    if memories:
        sections.append(f"相关记忆：\n{memories}")
    return "\n\n".join(sections)


_last_context_key, _last_prompt = None, None


def get_system_prompt(context: dict) -> str:
    global _last_context_key, _last_prompt
    key = json.dumps(context, sort_keys=True, ensure_ascii=False, default=str)
    if key == _last_context_key and _last_prompt:
        return _last_prompt
    _last_context_key = key
    _last_prompt = assemble_system_prompt(context)
    return _last_prompt


# ── 工具 ──

def safe_path(p: str) -> Path:
    path = (WORKDIR / p).resolve()
    if not path.is_relative_to(WORKDIR):
        raise ValueError(f"路径逃逸出工作区：{p}")
    return path


def run_bash(command: str, run_in_background: bool = False) -> str:
    # run_in_background 由 agent_loop 分发处理，不在这里处理
    try:
        r = subprocess.run(command, shell=True, cwd=WORKDIR,
                           capture_output=True, text=True, timeout=120)
        out = (r.stdout + r.stderr).strip()
        return out[:50000] if out else "（无输出）"
    except subprocess.TimeoutExpired:
        return "错误：执行超时（120 秒）"


def run_read(path: str, limit: int | None = None) -> str:
    try:
        lines = safe_path(path).read_text().splitlines()
        if limit and limit < len(lines):
            lines = lines[:limit] + [f"... ({len(lines) - limit} 行更多内容）"]
        return "\n".join(lines)
    except Exception as e:
        return f"错误：{e}"


def run_write(path: str, content: str) -> str:
    try:
        fp = safe_path(path)
        fp.parent.mkdir(parents=True, exist_ok=True)
        fp.write_text(content)
        return f"已写入 {len(content)} 字节到 {path}"
    except Exception as e:
        return f"错误：{e}"


# 任务工具

def run_create_task(subject: str, description: str = "",
                    blockedBy: list[str] | None = None) -> str:
    task = create_task(subject, description, blockedBy)
    deps = f"（依赖：{', '.join(blockedBy)}）" if blockedBy else ""
    print(f"  \033[34m[创建] {task.subject}{deps}\033[0m")
    return f"已创建 {task.id}: {task.subject}{deps}"


def run_list_tasks() -> str:
    个任务 = list_tasks()
    if not 个任务:
        return "暂无任务。请使用 create_task 添加任务。"
    lines = []
    for t in 个任务:
        icon = {"pending": "○", "in_progress": "●",
                "completed": "✓"}.get(t.status, "?")
        deps = f"（依赖：{', '.join(t.blockedBy)}）" if t.blockedBy else ""
        owner = f" [负责人：{t.owner}]" if t.owner else ""
        status = {"pending": "待处理", "in_progress": "进行中",
                  "completed": "已完成"}.get(t.status, t.status)
        lines.append(f"  {icon} {t.id}: {t.subject} "
                     f"[{status}]{owner}{deps}")
    return "\n".join(lines)


def run_get_task(task_id: str) -> str:
    try:
        return get_task(task_id)
    except FileNotFoundError:
        return f"错误：任务 {task_id} 未找到"


def run_claim_task(task_id: str) -> str:
    return claim_task(task_id, owner="agent")


def run_complete_task(task_id: str) -> str:
    return complete_task(task_id)


# ── 后台任务 （来自 s13，已同步） ──

_bg_计数器 = 0
background_tasks: dict[str, dict] = {}
background_results: dict[str, str] = {}
background_lock = threading.Lock()


def is_slow_operation(tool_name: str, tool_input: dict) -> bool:
    """兜底启发式：判断命令是否可能超过 30 秒。"""
    if tool_name != "bash":
        return False
    cmd = tool_input.get("command", "").lower()
    slow_keywords = ["install", "build", "test", "deploy", "compile",
                     "docker build", "pip install", "npm install",
                     "cargo build", "pytest", "make"]
    return any(kw in cmd for kw in slow_keywords)


def should_run_background(tool_name: str, tool_input: dict) -> bool:
    """模型的显式请求优先；否则使用启发式兜底。"""
    if tool_input.get("run_in_background"):
        return True
    return is_slow_operation(tool_name, tool_input)


def execute_tool(block) -> str:
    """执行工具调用块并返回输出。"""
    handler = {
        "bash": run_bash, "read_file": run_read, "write_file": run_write,
        "create_task": run_create_task, "list_tasks": run_list_tasks,
        "get_task": run_get_task, "claim_task": run_claim_task,
        "complete_task": run_complete_task,
        "schedule_cron": run_schedule_cron, "list_crons": run_list_crons,
        "cancel_cron": run_cancel_cron,
    }.get(block.name)
    if handler:
        return handler(**block.input)
    return f"未知工具：{block.name}"


def start_background_task(block) -> str:
    """在守护线程中运行工具，并返回后台任务 ID。"""
    global _bg_计数器
    _bg_计数器 += 1
    bg_id = f"bg_{_bg_计数器:04d}"
    cmd = block.input.get("command", block.name)

    def worker():
        result = execute_tool(block)
        with background_lock:
            background_tasks[bg_id]["status"] = "completed"
            background_results[bg_id] = result

    with background_lock:
        background_tasks[bg_id] = {
            "tool_use_id": block.id,
            "command": cmd,
            "status": "running",
        }
    threading.Thread(target=worker, daemon=True).start()
    print(f"  \033[33m[后台] 已分发 {bg_id}: {cmd[:40]}\033[0m")
    return bg_id


def collect_background_results() -> list[str]:
    """将已完成的后台结果收集为 task_notification 消息。"""
    with background_lock:
        ready_ids = [bid for bid, task in background_tasks.items()
                     if task["status"] == "completed"]
    notifications = []
    for bg_id in ready_ids:
        with background_lock:
            task = background_tasks.pop(bg_id)
            output = background_results.pop(bg_id, "")
        summary = output[:200] if len(output) > 200 else output
        notifications.append(
            f"<task_notification>\n"
            f"  <task_id>{bg_id}</task_id>\n"
            f"  <status>completed</status>\n"
            f"  <command>{task['command']}</command>\n"
            f"  <summary>{summary}</summary>\n"
            f"</task_notification>")
        print(f"  \033[32m[后台完成] {bg_id}: "
              f"{task['command'][:40]} ({len(output)} 个字符)\033[0m")
    return notifications


# ── Cron 调度器 （s14 新增） ──

DURABLE_PATH = WORKDIR / ".scheduled_tasks.json"


@dataclass
class CronJob:
    id: str
    cron: str        # "0 9 * * *"
    prompt: str      # 触发时要注入的消息
    recurring: bool  # 为真 = 重复，为假 = 一次性
    durable: bool    # 为真 = 持久化到磁盘


scheduled_jobs: dict[str, CronJob] = {}
cron_queue: list[CronJob] = []
cron_lock = threading.Lock()
agent_lock = threading.Lock()
_last_fired: dict[str, str] = {}  # job_id → "YYYY-MM-DD HH:MM"


def _cron_field_matches(field: str, value: int) -> bool:
    """将单个 cron 字段与一个值进行匹配。"""
    if field == "*":
        return True
    if field.startswith("*/"):
        step = int(field[2:])
        return step > 0 and value % step == 0
    if "," in field:
        return any(_cron_field_matches(f.strip(), value)
                   for f in field.split(","))
    if "-" in field:
        lo, hi = field.split("-", 1)
        return int(lo) <= value <= int(hi)
    return value == int(field)


def cron_matches(cron_expr: str, dt: datetime) -> bool:
    """检查 5 字段 cron 表达式是否匹配给定时间。
    标准 cron 语义：月内日和周内日同时受限时，两者使用 OR。"""
    fields = cron_expr.strip().split()
    if len(fields) != 5:
        return False
    minute, hour, dom, month, dow = fields
    dow_val = (dt.weekday() + 1) % 7  # Python Monday=0 → cron Sunday=0

    m = _cron_field_matches(minute, dt.minute)
    h = _cron_field_matches(hour, dt.hour)
    dom_ok = _cron_field_matches(dom, dt.day)
    month_ok = _cron_field_matches(month, dt.month)
    dow_ok = _cron_field_matches(dow, dow_val)

    # 分钟、小时、月份必须全部匹配
    if not (m and h and month_ok):
        return False
    # DOM 和 DOW：如果两者都有限制，任一匹配即可（OR）
    dom_unconstrained = dom == "*"
    dow_unconstrained = dow == "*"
    if dom_unconstrained and dow_unconstrained:
        return True
    if dom_unconstrained:
        return dow_ok
    if dow_unconstrained:
        return dom_ok
    return dom_ok or dow_ok


def _validate_cron_field(field: str, lo: int, hi: int) -> str | None:
    """校验单个 cron 字段值是否位于 [lo, hi] 范围内。"""
    if field == "*":
        return None
    if field.startswith("*/"):
        step_str = field[2:]
        if not step_str.isdigit():
            return f"无效步长：{field}"
        step = int(step_str)
        if step <= 0:
            return f"步长必须 > 0：{field}"
        return None
    if "," in field:
        for part in field.split(","):
            err = _validate_cron_field(part.strip(), lo, hi)
            if err: return err
        return None
    if "-" in field:
        parts = field.split("-", 1)
        if not parts[0].isdigit() or not parts[1].isdigit():
            return f"无效范围：{field}"
        a, b = int(parts[0]), int(parts[1])
        if a < lo or a > hi or b < lo or b > hi:
            return f"范围 {field} 超出边界 [{lo}-{hi}]"
        if a > b:
            return f"范围起点大于终点：{field}"
        return None
    if not field.isdigit():
        return f"无效字段：{field}"
    val = int(field)
    if val < lo or val > hi:
        return f"值 {val} 超出边界 [{lo}-{hi}]"
    return None


def validate_cron(cron_expr: str) -> str | None:
    """校验 cron 表达式。返回错误消息或 None。"""
    fields = cron_expr.strip().split()
    if len(fields) != 5:
        return f"期望 5 个字段，实际得到 {len(fields)}"
    bounds = [(0, 59), (0, 23), (1, 31), (1, 12), (0, 6)]
    names = ["分", "时", "月内日", "月", "周内日"]
    for i, (field, (lo, hi), name) in enumerate(zip(fields, bounds, names)):
        err = _validate_cron_field(field, lo, hi)
        if err:
            return f"{name}: {err}"
    return None


def save_durable_jobs():
    """将持久任务保存到 .scheduled_tasks.json。"""
    durable = [asdict(j) for j in scheduled_jobs.values() if j.durable]
    DURABLE_PATH.write_text(json.dumps(durable, indent=2))


def load_durable_jobs():
    """启动时从磁盘加载持久任务。"""
    if not DURABLE_PATH.exists():
        return
    try:
        jobs = json.loads(DURABLE_PATH.read_text())
        for j in jobs:
            job = CronJob(**j)
            err = validate_cron(job.cron)
            if err:
                print(f"  \033[31m[cron] 跳过无效任务 {job.id}: {err}\033[0m")
                continue
            scheduled_jobs[job.id] = job
        valid = [j for j in jobs if j["id"] in scheduled_jobs]
        if valid:
            print(f"  \033[35m[cron] 已加载 {len(valid)} 个持久任务\033[0m")
    except Exception:
        pass


def schedule_job(cron: str, prompt: str, recurring: bool = True,
                 durable: bool = True) -> CronJob | str:
    """注册一个新的 cron 任务。返回 CronJob 或错误字符串。"""
    err = validate_cron(cron)
    if err:
        return err
    job = CronJob(
        id=f"cron_{random.randint(0, 999999):06d}",
        cron=cron, prompt=prompt,
        recurring=recurring, durable=durable,
    )
    with cron_lock:
        scheduled_jobs[job.id] = job
    if durable:
        save_durable_jobs()
    print(f"  \033[35m[cron 注册] {job.id} '{cron}' → {prompt[:40]}\033[0m")
    return job


def cancel_job(job_id: str) -> str:
    """取消一个 cron 任务。"""
    with cron_lock:
        job = scheduled_jobs.pop(job_id, None)
    if not job:
        return f"任务 {job_id} 未找到"
    if job.durable:
        save_durable_jobs()
    print(f"  \033[31m[cron 取消] {job_id}\033[0m")
    return f"已取消 {job_id}"


def cron_scheduler_loop():
    """独立守护线程：每秒轮询一次并触发匹配任务。
    单个任务出错会被捕获，避免整个调度线程退出。"""
    while True:
        time.sleep(1)
        now = datetime.now()
        # 带日期感知的标记，防止每日任务从第 2 天起被跳过
        minute_marker = now.strftime("%Y-%m-%d %H:%M")
        with cron_lock:
            for job in list(scheduled_jobs.values()):
                try:
                    if cron_matches(job.cron, now):
                        if _last_fired.get(job.id) != minute_marker:
                            cron_queue.append(job)
                            _last_fired[job.id] = minute_marker
                            print(f"  \033[35m[cron 触发] {job.id} → "
                                  f"{job.prompt[:40]}\033[0m")
                        if not job.recurring:
                            scheduled_jobs.pop(job.id, None)
                            if job.durable:
                                save_durable_jobs()
                except Exception as e:
                    print(f"  \033[31m[cron 错误] {job.id}: {e}\033[0m")


def consume_cron_queue() -> list[CronJob]:
    """消费 cron_queue 中已触发的任务（由 agent_loop 调用）。"""
    with cron_lock:
        fired = list(cron_queue)
        cron_queue.clear()
    return fired


def has_cron_queue() -> bool:
    """返回是否有已触发但尚未投递的 cron 任务。"""
    with cron_lock:
        return bool(cron_queue)


# 启动时加载持久任务，然后启动调度线程
load_durable_jobs()
threading.Thread(target=cron_scheduler_loop, daemon=True).start()
print("  \033[35m[cron] 调度线程已启动\033[0m")


# ── Cron 工具 ──

def run_schedule_cron(cron: str, prompt: str,
                      recurring: bool = True, durable: bool = True) -> str:
    result = schedule_job(cron, prompt, recurring, durable)
    if isinstance(result, str):
        return f"错误：{result}"
    return f"已调度 {result.id}: '{cron}' → {prompt}"


def run_list_crons() -> str:
    with cron_lock:
        jobs = list(scheduled_jobs.values())
    if not jobs:
        return "暂无 cron 任务。请使用 schedule_cron 添加一个。"
    lines = []
    for j in jobs:
        tag = "重复" if j.recurring else "一次性"
        dur = "持久化" if j.durable else "仅本会话"
        lines.append(f"  {j.id}: '{j.cron}' → {j.prompt[:40]} "
                     f"[{tag}, {dur}]")
    return "\n".join(lines)


def run_cancel_cron(job_id: str) -> str:
    return cancel_job(job_id)


# ── 工具定义 ──

TOOLS = [
    {"name": "bash", "description": "运行一条 shell 命令。",
     "input_schema": {"type": "object",
                      "properties": {
                          "command": {"type": "string"},
                          "run_in_background": {"type": "boolean"}},
                      "required": ["command"]}},
    {"name": "read_file", "description": "读取文件内容。",
     "input_schema": {"type": "object",
                      "properties": {"path": {"type": "string"},
                                     "limit": {"type": "integer"}},
                      "required": ["path"]}},
    {"name": "write_file", "description": "向文件写入内容。",
     "input_schema": {"type": "object",
                      "properties": {"path": {"type": "string"},
                                     "content": {"type": "string"}},
                      "required": ["path", "content"]}},
    {"name": "create_task",
     "description": "创建一个新任务，可选 blockedBy 依赖。",
     "input_schema": {"type": "object",
                      "properties": {
                          "subject": {"type": "string"},
                          "description": {"type": "string"},
                          "blockedBy": {"type": "array",
                                        "items": {"type": "string"}}},
                      "required": ["subject"]}},
    {"name": "list_tasks",
     "description": "列出所有任务及其状态、负责人和依赖。",
     "input_schema": {"type": "object", "properties": {},
                      "required": []}},
    {"name": "get_task",
     "description": "按 ID 获取指定任务的完整详情。",
     "input_schema": {"type": "object",
                      "properties": {"task_id": {"type": "string"}},
                      "required": ["task_id"]}},
    {"name": "claim_task",
     "description": "认领一个待处理任务。设置 owner，并将状态改为 in_progress。",
     "input_schema": {"type": "object",
                      "properties": {"task_id": {"type": "string"}},
                      "required": ["task_id"]}},
    {"name": "complete_task",
     "description": "完成一个进行中的任务。报告被解除阻塞的下游任务。",
     "input_schema": {"type": "object",
                      "properties": {"task_id": {"type": "string"}},
                      "required": ["task_id"]}},
    {"name": "schedule_cron",
     "description": "调度一个 cron 任务。cron 为 5 字段：分 时 月内日 月 周内日。",
     "input_schema": {"type": "object",
                      "properties": {
                          "cron": {"type": "string",
                                   "description": "5 字段 cron 表达式"},
                          "prompt": {"type": "string",
                                     "description": "触发时要注入的消息"},
                          "recurring": {"type": "boolean",
                                        "description": "为真表示重复，为假表示一次性"},
                          "durable": {"type": "boolean",
                                      "description": "为真表示持久化到磁盘"}},
                      "required": ["cron", "prompt"]}},
    {"name": "list_crons",
     "description": "列出所有已注册的 cron 任务。",
     "input_schema": {"type": "object", "properties": {},
                      "required": []}},
    {"name": "cancel_cron",
     "description": "按 ID 取消 cron 任务。",
     "input_schema": {"type": "object",
                      "properties": {"job_id": {"type": "string"}},
                      "required": ["job_id"]}},
]


# ── 上下文 ──

def update_context(context: dict, messages: list) -> dict:
    """从真实状态推导上下文。"""
    memories = ""
    if MEMORY_INDEX.exists():
        content = MEMORY_INDEX.read_text().strip()
        if content:
            memories = content
    return {
        "enabled_tools": [t["name"] for t in TOOLS],
        "workspace": str(WORKDIR),
        "memories": memories,
    }


# ── Agent 循环（简化版，聚焦 cron 调度器） ──
# 教学代码保留基础 Agent 循环。省略 S11 的完整错误恢复。
# cron_scheduler_loop 产出任务；当
# 存在排队任务且没有其他 Agent 轮次运行时，queue_processor_loop 会唤醒该循环。

def agent_loop(messages: list, context: dict) -> dict:
    system = get_system_prompt(context)
    while True:
        # 第 4 层：消费已触发的 cron 任务 → 作为消息注入
        fired = consume_cron_queue()
        for job in fired:
            messages.append({"role": "user",
                             "content": f"[已调度] {job.prompt}"})
            print(f"  \033[35m[注入 cron] {job.prompt[:50]}\033[0m")

        try:
            response = client.messages.create(
                model=MODEL, system=system, messages=messages,
                tools=TOOLS, max_tokens=8000)
        except Exception as e:
            messages.append({"role": "assistant", "content": [
                {"type": "text",
                 "text": f"[错误] {type(e).__name__}: {e}"}]})
            return context

        messages.append({"role": "assistant", "content": response.content})
        if response.stop_reason != "tool_use":
            return context

        results = []
        for block in response.content:
            if block.type != "tool_use":
                continue
            print(f"\033[36m> {block.name}\033[0m")

            if should_run_background(block.name, block.input):
                bg_id = start_background_task(block)
                results.append({"type": "tool_result",
                                "tool_use_id": block.id,
                                "content": f"[后台任务 {bg_id} 已启动] "
                                           f"完成后结果将可用。"})
            else:
                output = execute_tool(block)
                print(str(output)[:300])
                results.append({"type": "tool_result",
                                "tool_use_id": block.id,
                                "content": output})

        # 将后台工具结果 + 通知合并成一条用户消息
        user_content = list(results)
        bg_notifications = collect_background_results()
        if bg_notifications:
            for notif in bg_notifications:
                user_content.append({"type": "text", "text": notif})
        messages.append({"role": "user", "content": user_content})
        context = update_context(context, messages)
        system = get_system_prompt(context)


session_history: list = []
session_context = update_context({}, [])


def print_latest_assistant_text(messages: list):
    """打印最新 assistant 消息中的文本块。"""
    if not messages:
        return
    msg = messages[-1]
    if not isinstance(msg, dict) or msg.get("role") != "assistant":
        return
    content = msg.get("content", "")
    if isinstance(content, str):
        print(content)
        return
    for block in content:
        if getattr(block, "type", None) == "text":
            print(block.text)
        elif isinstance(block, dict) and block.get("type") == "text":
            print(block.get("text", ""))


def run_agent_turn_locked(user_query: str | None = None):
    """运行一轮 Agent。调用方必须持有 agent_lock。"""
    global session_context
    if user_query is not None:
        session_history.append({"role": "user", "content": user_query})
    session_context = agent_loop(session_history, session_context)
    session_context = update_context(session_context, session_history)
    print_latest_assistant_text(session_history)
    print()


def queue_processor_loop():
    """当 Agent 空闲时自动投递已触发的 cron 任务。"""
    global session_context
    while True:
        time.sleep(0.2)
        if not has_cron_queue():
            continue
        if not agent_lock.acquire(blocking=False):
            continue
        try:
            if not has_cron_queue():
                continue
            print("\n  \033[35m[队列处理器] 正在投递调度任务\033[0m")
            run_agent_turn_locked()
        finally:
            agent_lock.release()


if __name__ == "__main__":
    print("s14: cron 调度器")
    print("输入问题后按回车发送。输入 q 退出。\n")
    threading.Thread(target=queue_processor_loop, daemon=True).start()
    print("  \033[35m[队列处理器] 已启动\033[0m")
    while True:
        try:
            query = input("\033[36ms14 >> \033[0m")
        except (EOFError, KeyboardInterrupt):
            break
        if query.strip().lower() in ("q", "exit", ""):
            break
        with agent_lock:
            run_agent_turn_locked(query)